Total anatomic hip prosthesis

• US 5,725,593 A
• Filed: 10/30/1996
• Issued: 03/10/1998
• Est. Priority Date: 02/22/1995
• Status: Expired due to Fees

• Current Assignee: Francesco Caracciolo
• Original Assignee: Francesco Caracciolo
• Inventors: Caracciolo, Francesco
• Primary Examiner(s): Weiss, John G.
• Assistant Examiner(s): SNOW, BRUCE EDWARD
• Application Number:
  US08/739,929
• Time in Patent Office: 496 Days
• Field of Search: 623/18, 623/22, 623/23, 606/65, 606/70
• US Class Current: 623/22.23
• CPC Class Codes: A61B 17/742 having one or more longitudinal elements oriented along or parallel to the axis of the neck
• CPC Class Codes: A61B 17/80 Cortical plates , i.e. bone plates; Instruments for holding or positioning cortical plates, or for compressing bones attached to cortical plates
• CPC Class Codes: A61B 17/8665 Nuts
• CPC Class Codes: A61B 17/8695 Washers surrounding screw head in plate hole A61B17/8047, between bone plate and bone A61B17/8028
• CPC Class Codes: A61F 2/30739 Devices connected to the proximal part of an endoprosthetic femoral shaft for reinforcing or replacing the trochanters, e.g. the greater trochanter proximal parts of endoprosthetic femoral shafts A61F2/367; non-prosthetic trochanteric devices A61B17/74
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/3601 for replacing only the epiphyseal or metaphyseal parts of the femur, e.g. endoprosthetic femoral heads or necks directly fixed to the natural femur by internal fixation devices non-prosthetic internal fixation devices for the femoral head or neck A61B17/74
• CPC Class Codes: A61F 2/3603 implanted without ablation of the whole natural femoral head endoprosthetic cartilage A61F2/30756
• CPC Class Codes: A61F 2/367 Proximal or metaphyseal parts of shafts trochanteric devices connected to said proximal parts A61F2/30739
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2002/30112 Rounded shapes, e.g. with rounded corners
• CPC Class Codes: A61F 2002/30153 rectangular
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30367 with additional means for preventing said rotation
• CPC Class Codes: A61F 2002/30426 Bayonet coupling
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30535 Special structural features of bone or joint prostheses not otherwise provided for
• CPC Class Codes: A61F 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30673 Lubricating means, e.g. synovial pocket
• CPC Class Codes: A61F 2002/30787 inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/30797 : internally-threaded
• CPC Class Codes: A61F 2002/30836 : knurled
• CPC Class Codes: A61F 2002/30841 : Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30845 : with cutting edges
• CPC Class Codes: A61F 2002/30878 : with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2002/30879 : Ribs
• CPC Class Codes: A61F 2002/30894 : inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/30904 : serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/30934 : Special articulating surfaces
• CPC Class Codes: A61F 2002/3208 : Bipolar or multipolar joints, e.g. having a femoral head articulating within an intermediate acetabular shell whilst said shell articulates within the natural acetabular socket or within an artificial outer shell
• CPC Class Codes: A61F 2002/3241 : having a ring, e.g. for locking the femoral head into the acetabular cup
• CPC Class Codes: A61F 2002/3403 : Polar aperture
• CPC Class Codes: A61F 2002/3417 : the outer shell having protrusions on meridian lines, e.g. equidistant fins or wings around the equatorial zone
• CPC Class Codes: A61F 2002/3613 : with lateral or oblique apertures, holes or openings
• CPC Class Codes: A61F 2002/3621 : pierced with a longitudinal bore
• CPC Class Codes: A61F 2210/0019 : operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2230/0004 : Rounded shapes, e.g. with rounded corners
• CPC Class Codes: A61F 2230/0019 : rectangular
• CPC Class Codes: A61F 2250/0058 : Additional features; Implant or prostheses properties not otherwise provided for

Abstract

It is described a total anatomic hip prosthesis including a hemispherical prosthetic acetabulum standing above a hemispherical cap, both provided with anchorage means fitting by pressure the acetabulum in the iliac fossa and, respectively, the cap on femoral head, said cap being linked to the components that hold it permanently on said femoral head.

Claims

1. Total anatomic hip prosthesis for patients who do not need the femoral head removed, which comprises a hemispherical prosthetic acetabulum, a hemispherical cap insertable into a cavity inside said acetabulum and a stabilizing ring positioned outside said acetabulum and connectable thereto, said acetabulum adapted to fit in said iliac fossa through said stabilizing ring which includes a junction and is provided on its external circumference with hooks, said cap being provided with anchorage means for fitting by pressure on said femoral head, an outside surface of said cap having round projections to reduce the friction with the inner surface of said cavity inside said acetabulum, said cap being further connected with holding means adapted to hold it stably on the femoral head.

2. The prosthesis according to claim 1, wherein the top of said prosthetic acetabuhm has a control opening or hole for technical and biological application purposes.

3. The prosthesis according to claim 1, wherin said anchorage means of said cap with said femoral head consists of a notching realized along the whole rim of said cap.

4. The prosthesis according to claim 3, wherein on the top of said cap there is a seat with a central opening or hole.

5. The prosthesis according to claim 1, wherein inside said cap there is an alveolate structure with holes which communicate with the outside surface of said cap.

6. The prosthesis according to claim 1, wherein said round projections are radial grains, segments having a hemispherical or a different shape or sliding blocks.

7. The prosthesis according to claim 1, wherein said stabilizing ring includes cavities which include an inclined plane placed on the inner surface of said ring which allow the fitting and the passage of radial projections on the external surface of said acetabulum which, rotating, connect said acetabulum to said stabilizing ring.

8. The prosthesis according to claim 1, wherein said stabilizing ring is made of a "shape-memorizing" material.

9. The prosthesis according to claim 1, wherein said holding means adapted to hold said cap on said femoral head include a higher blind compensator which is threaded inside and is provided with a head, a stirrup, a lower passing compensator and a tie.

10. The prosthesis according to claim 9, wherein said tie is provided with a head on a first end and with a threading on the opposite end.

11. A prosthesis according to claim 9, wherein said tie is inserted in said lower passing compensator, then in said stirrup and sized to penetrate from the top of the femoral diaphysis under the great trochanter, it passes obliquely through the whole higher femoral epiphysis and through the center of the femoral neck and head in order to be screwed to said higher blind compensator, whose head placed in said seat of said cap constrains all.

12. The prosthesis according to claim 9, wherein said stirrup has a structural C-shape reproducing the shape of the external and lateral cortex of the femur under the great trochanter and wherein said stirrup is provided with a niche with a central and oblong opening apt to house said lower passing compensator, having a flat side and a convex side, and said head of said tie.

13. The prosthesis according to claim 12, wherein said convex side of said lower passing compensator and said central oblong opening of said niche of said stirrup allow said tie to rotate together with said lower passing compensator with reference to said stirrup to adapt said prosthesis to the specific geometrical characteristics of the patient'"'"'s femur.

14. The prosthesis according to claim 1, wherein all components of said prosthesis are made of a defined "inert", highly biocompatible material.

15. The prosthesis according to claim 1, wherein said round projections are circular rises.